Pond aerators are devices designed to increase the oxygen levels within a pond by circulating the water. They work by creating bubbles or waves, which helps to mix the water layers and prevent stratification. This process is crucial for maintaining a balanced, healthy environment for all pond inhabitants, from fish to beneficial bacteria. There are several types of aerators, including surface aerators, which create a fountain-like effect, and subsurface diffused aerators, which release bubbles from the bottom of the pond.